Blister copper produced in converters or direct to blister furnaces is purified of sulfur and oxygen before it can be cast to anodes. This is done in anode furnaces (AF) in a process known as fire refining. In addition to refining blister copper to anode copper, the anode furnace may be used for melting solid copper such as copper scrap from the refinery and in-house anode copper scrap. However, conventional anode furnaces have very limited capacity to melt solid copper during operation. Thus typically copper scrap is melted in separate copper scrap furnaces.
WO2011/103132 discloses a method for anode refining of copper wherein molten blister copper is first provided to a furnace, then copper scrap is charged to the molten blister copper in the furnace, and finally charged copper scrap is melted and charged molten blister copper is heated using a melting flame produced from a top-blown multi-functional coherent jet lance. Multi-functional coherent jet lances require high pressure oxygen and high pressure nitrogen which are expensive to use and generally not easily available at a smelter. Also cooling water demand is high.